Low bit-rate speech coder using adaptive open-loop subframe pitch lag estimation and vector quantization
US6345248B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 2, 1999 |
| Grant date | Feb 5, 2002 |
| Priority date | — |
| Expiry date | Nov 2, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L2019/0011
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A pitch lag coding device and method using interframe correlation inherent in pitch lag values to reduce coding bit requirements. A pitch lag value is extracted for a given speech frame, and then refined for each subframe. For every speech frame having N samples of speech, LPC analysis and vector quantization are performed for the whole coding frame. The LPC residual obtained for each frame is then processed such that pitch lag values for all subframes within the coding frame are analyzed concurrently. The remaining coding parameters, i.e., the codebook search, gain parameters, and excitation signal, are then analyzed sequentially according to their respective subframes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.